Motor operated valve



Filed Dec. 15, 1930 ATTORNEY;

, burning unit showing Patented Sept. 1, 1936 PATENT OFFICE 2,052,918MOTOR OPERATED VALVE Nelson T. Branche,

Toledo, Ohio, assignor,

mesne assignments, to Minneapolis-Honeywell Regulator Company,Minneapolis, Minn., a

corporation of Delaware Application December 13, 1930, Serial No.502,120 17 Claims. (Cl. 137-139) This invention relates to improvementsin motor-operated valves and more particularly to valve-operatingmechanism for valves which are biased toward closed position. Valves ofthis type have special utility with gas burning apments hereinafter morefully set forth.

Referring to the drawing wherein the preferred embodiment of theinvention is shown:

Fig. 1 is a fragmentary side elevation of a gas how the improved valveis associated therewith;

Fig. 2 is a sectional elevation of the valve and operating mechanismtherefor, the section being taken on line 2-2 of Fig. 4;

Fig. 3 is an elevation of the valve with a side wall removed, the viewbeing taken on line 3-3 of Fig. 4;

Fig. 4 is a plan view of the valve operating mechanism with the housingremoved;

Fig. 5 is a view of a detail of the device, the view being taken on line55 of Fig. 4;

Fig. 6 is an enlarged detail view of parts shown in Fig. 2, and

Fig. 7 is an electrical diagram showing a simple circuit for connectingthe device for operation with a domestic house heating unit.

In the drawing, 10 indicates a box-like conduit forming part of a gasburner and having a secondary air opening normally closed by damper i I.Combustible mixture is supplied to the burners (not shown) by a pipe l2which leads from a mixing tube l3, gas being delivered to the mixingtube from the gas valve generally indicated at H. Air for mixing withthe gas is controlled by an air shutter I 5 at the front of the conduit,said front being closed by a casting l6 having formed thereinappropriate passages for delivering the air and gas to the mixing tube.The burner apparatus itself forms no part of the present invention buthas been briefly described merely to indicate the environment whereinthe invention finds special utility.

The gas valve is either fully open or closed, depending upon heatrequirements. When the gas valve is open, the secondary air damper I lis also open and vice versa, appropriate connections being providedbetween the damper and valve operating mechanism to effect this result.The connection preferably comprises a lever I! one end of which isconnected to the damper by a spring I8 and the other end of which issuitably connected to the valve operating mechanism hereinafterdescribed. The lever I! is also utilized for manually opening the valvein case of current failure to the valve opening motor.

The gas valve comprises a valve casing l9 having inlet and outletconnections 20 and 2| and having a dividing partition 22 provided withthe passage 23 forming a valve seat. The valve is indicated at 24 andits valve stem at 25, the valve being hinged to the stem as indicated at26. A spring 27 interposed between the valve and a body 28 at the top ofvalve casing serves to normally hold the valve secured to the valvecasing by a collar 29. Supported by said body 28 is a bowl-like member30 across the top of which extends a flexible diaphragm 3| through thecenter of which the valve stem passes in a gas tight manner, thediaphragm providing an effective seal between the valve chamber and theexterior operating mechanism.

The valve-operating mechanism is mounted upon two spaced upright plates32 and 33 secured to a base plate 34 supported by the member 30. Thevalve-operating motor is secured to the plate 32 by laterally extendingmembers 35. The motor field is indicated at 36, the poles at 31, therotor at 38, and the rotor shaft at 39. This shaft projects through theplate 32' and has secured thereto a pinion 40. This pinion drives a geartrain which in turn actuates the valve stem 25 by means of a crank andlever arrangement. The final driven gear is indicated at 4|. Secured tothis gear is a crank arm 42. The lever i1 previously mentioned isconnected with the valve stem 25 by a pin and slot connection 43.Connecting the crank arm 42 and lever I 1 is a link 44 having a lostmotion connection 45. The lever is pivotally mounted on a rod 46 whichis supported by the side plates 32 and 33.

Delivery of current to the motor will cause its rotor 38 to revolve withresultant opening of the valve 24 as willnow be readily understood.Since the lever I1 is part of the valve-operating mechanism and sincethis lever is connected to the damper II, it follows that the damperwill be operated in unison with the valve 24.

In the ordinary type of motor operated valve, current continues to flowthrough the motor after the valve has been opened, otherwise the spring2'! would immediately close the valve, the gear train being such as topermit the spring to rotate the gear train. The present invention,however,

provides means for cutting 01f the current to theto its seat. Said bodyis removably 15 motor after the valve has been opened and provides amagnetically operated brake for preventing the spring from closing thevalve.

Referring to Figs. 3, 4 and 5 wherein the preferred form of brakingmechanism is shown, 41 indicates an electro magnet, the core 48 of whichis supported by the side plate 32. The armature is an arm 49 hinged atone end as at 50 to an extension from the core 48. The arm 49 isprovided at its outer end with a piece of copper plate 49' which acts asa choke or dam in the lines of the magnetic force. Thus fluctuation ofthe magnetic force due to the pulsations of the alternating current isprevented, as will be readily understood by those skilled in the art,and chattering or vibrating of the arm is prevented. Secured to the arm49 and projecting laterally therefrom is a spring blade 5|. Secured tothe rotor shaft 39 is a brake disk 52. A brake lever is indicated at 53and its shoe at 54, the lever being pivoted on a suitable support 55between the plate 32 and the pole leg 31 of the motor. The upper end ofthe lever is slotted as indicated at 55 and the spring blade 5| extendsinto the slot. When the armature arm 49 is attracted by the magnet thefree end of the blade 5| moves to the right as viewed in Figs. 4 and 5and applies the brake by actuating the brake lever 53 as will now beunderstood. The spring blade 5| obviously provides a yielding connectionbetween the armature arm 49 and the brake lever 53. When current to theelectro magnet is cut off the brake automatically releases. Since thebrake disk 52 is attached to the motor shaft 39, the motor iseflectually kept from rotating and the valve is maintained in its openposition when current to the motor is cut off.

As soon, however, as current is shut off from the electro magnet, thevalve spring 21 will close the valve, the spring being sufficientlystrong to overcome the inertia of the motor and train of gear and drivethe valve down with considerable force, thereby insuring a completeseating of the valve. By providing a lost motion connection between thecrank 42 and the valve stem as indie cated at 45, rotation of the motorand gear train under the influence of the valve spring is notimmediately stopped and consequently not only is there less strain onthe mechanism but rebound of the valve incident to reversal of rotationof the gear train and motor following sudden stopping of rotation iseffectually prevented. Means for exerting some frictional resistance onthe rotating parts may also be provided as by a leaf spring 51 arrangedto press on the end of the rotor shaft.

The means for cutting off the current to the valve operating motor andadmitting current to the brake operating electro magnet will next bedescribed. Mounted for rotation with the topmost shaft of the gear trainis a cam 58 comprising a circular disk having a notch 59 in itsperiphery. Said shaft rotates approximately 300 during the opening ofthevalve. 59 indicates a leaf spring switch-arm the upper end of whichalways bears on the cam and the lower end of which is secured to abracket 6!. Also secured to said bracket are two spring switch arms 62and 63. Arms 60 and 62 are in electrical contact when arm 60 is out ofthe cam notch 59 and arms 60 and 63 are in electrical contact when arm50 is in said notch. Wires 60', 62, and 63 lead from the respectiveswitch arms. The arrow on the cam indicates the direction of rotation inopening the valve.

Fig. 7 shows a wiring diagram for the apparatus in connection with aroom thermostat. In the diagram, the valve operating motor is indicatedat M and the brake-operating electro magnet at E. A room thermostat isindicated at RT and T indicates the source of power which in the presentcase is a transformer. The equivalent of cam 58 is indicated at C. Whenthe thermostat at RT closes, current will flow to the motor M to openthe valve, it being noted that the cam C meanwhile maintains the switcharm 60 at the left to keep the motor circuit closed. The cam rotates inthe direction of the arrow adjacent thereto. When the valve has openedthe cam will permit the switch arm 69 to move to the right to break themotor circuit and make the electro magnet circuit. When the thermostatopens the electro'magnet is deenergized, whereupon the valve spring willclose the valve as will now be readily understood.

In case there should be a failure of current, the

valve may, nevertheless, be manually opened in the following manner andby the following described means. The outer end of the lever I1 isdepressed whereupon the valve will open and the crank-carrying gear 4|given a partial rotation. On this gear is a latch pin 64 with which alatch arm 65 may be engaged by pushing on a push rod 66 mounted in awall of the housing 61 wherein the operating mechanism is contained. Aspring blade 68 normally holds the latch arm in retracted position. Thepin 64 is so placed on the gear that when it is latched the gear maystill be rotated a few degrees in a valve opening direction andconsequently when current 35 is again effective at the motor the gearwill be rotated sufficiently to automatically release the latch. To putthe, matter in another way the pin 64 is so located that the switch arm60 does not enter the cam notch 59. The spring 69 also serves as aswitch arm which when the latch is closed makes contact with a switchblade 69. When this switch is closed the room thermostat is shunted out(see Fig. 7) with the result that even if the room thermostat should bein open position, current will flow to the motor and rotate itsufiiciently to cause release of the latch 65 whereupon the motorcircuit is broken and the valve spring will close the valve. In case theroom thermostat is closed the motor will continue to operate until theswitch arm 60 enters the cam notch 59 and thus transfers the current tothe electro magnet which operates the brake.

What I claim is:

1. In a valve operating mechanism the combination of a valve which willautomatically close unless positively held open, of a motor adapted tomove the valve to open position when power is applied to the motor,holding means adapted when power is applied thereto to prevent reversalof the motor when power thereto is cut off, control means for said motoroperable upon actuation thereof to apply power to said motor but not tosaid holding means. to open said valve, further means operable uponmovement thereof in one direction to first cut off power to the motorand then to apply power to the holding means, and means having anoperable connection with said valve and movable therewith, said last 72. In a valve operating mechanism. the com v rs aosaora bination with avalve which will automatically close unless positively held open, 01' amotor venting reversal of the motor when power thereto 3. In a valveoperating mechanism, the combination with a valve which willautomatically close unless positively held open, oi. a rotary electricmotor adapted to open the valve when power is applied to the motor, of afriction brake adapted to prevent said valve from closing, anelectromagnet adapted to actuate said brake, and means power to themotor after it has fully opened the valve and applying power to saidelectromagnet whereby the brake may be applied for the purposespecified.

4. In a valve operating mechanism, the combination with a valve whichwill automatically close unless positively held electric motor adaptedwhen brake adapted to prevent said valve from closing, an electromagnetadapted when energized to apply the brake, and means for first cuttingoff power to said motor and then closing the circuit valve by saidmotor.

5. In the combination claimed in claim 4, said brake acting on the rotorof said motor.

6. In a valve operating mechanism, the combination with a valve whichwill automatically close unless positively held open, of a rotaryelectric motor adapted when energized to open the for supplying power tothe electromagnet when power to the motor is cut oil, means connectingsaid brake and electromagnet comprising a pivoted armature, a springblade extending from the armature, and a brake lever adapted to be movedby said blade to apply the brake.

7. In a valve operating mechanism, the combination with a valve holdingmeans, means permitting manual opening of the valve in the event poweris not available for the motor, means for latching the valve in lessthan maximum open position following manual opening, a main switchadapted to close the power circuit to the motor, a second switchoperable by said latching means to shunt out said main switch andestablish the power circuit to the motor whereby when power is againavailable the motor will be energized irrespective of whether the mainswitch is closed, the vmotor when energized through the circuitembodying the second switch completing the maximum opening of the valve,and means for automatically releasing said latching means and openingsaid second switch when the valve is additionally opened by said motor;

8. In a valve operating mechanism, the combination with a valve whichwill automatically close unless positively held open, said valve havinga stem, 01' a rotary electric motor adapted energized to open theconnecting said motor and valve stem comprising a crank, a lost motionconnection connecting the crank and valve stem, and a gear trainconnecting the motor and crank.

9. In a valve operating mechanism, the combination with a andoperatively connected to said valve stem, the connection between saidcrank and valve stem including a lever for opening the valve by hand inthe event of current failure to the motor, and means operable to latchthe valve in open position following manual opening thereof.

valve and meansin combination, a fluid flow controlling element biasedto one flow controlling position, a lever, means pivotally mounting thesame, means connecting said lever to said fluid flow controlling elementat a point'spaced from the pivot point of said lever, a lower operatedactuator, a reducconnecting said gear train to said lever at a pointspaced from the point at which said fluid flow controlling element isconnected to said lever so that upon power being supplied-to saidactuator said fluid flow controlling element is moved to a second flowcontrolling position, said connecting means permitting relative movementbetween said reduction gearing and said lever, said lever being providedwith a portion adapted to be manually operated to permit said fluid flowcontrolling element to be manually moved to substantially said secondflow controlling position upon power failure, and manually operatedlatching means for maintaining said element in said last named positionupon being so moved.

14. A device of the class described, comprising in combination, a valvecasing having an inlet and an outlet, a partition wall therebetweenhaving a valve opening therein, a valve adapted to close said valveopening and biased to valve closing position, operating means connectedto said valve and movable upon operation thereof in one direction foropening said valve against its bias, the bias of the valve beingsuflicient to move said operating means during the valve closingoperation in the opposite direction at such a speed and through a largeenough range that the resulting momentum would be sufiicient to causethe valve to rebound from valve closing position upon reaching the same,and means for preventing such rebounding of the valve due to themomentum thus imparted to the operating means during valve closingmovement, said means comprising a friction brake acting on saidoperating means and effective to retard the movement thereof in valveclosing direction.

15. A device of the class described, comprising in combination, a valvecasing having an inlet and an outlet, a partition wall therebetweenhaving a valve opening therein, a valve adapted to close said valveopening and biased to valve closing position, operating means connectedto said valve and movable upon operation thereof in one direction foropening said valve against its bias, the bias of the valve beingsufficient to move said operating means during the valve closingoperation in the opposite direction at such a speed and through a largeengugh range that the retion gear train connected to said actuator,means upon reaching the same, and means for prevent- I ing suchrebounding of the valve due to the momentum thus imparted to theoperating means during valve closing movement, said means comprising alost motion connection between said operating means and said valve and abrake acting on said operating means and effective to retard themovement thereof in valve closing direction.

16. A device of the class described, comprising a valve casing having aninlet and an outlet, a partition wall therebetween having a valve seatformed therein, a valve normally biased against the seat to obstructfluid flow from the inlet to the outlet, a rotating actuator for thevalve, 9. gear train between said actuator and valve whereby the lattermay be opened against its bias by the former upon operative energizationthereof, the bias of the valve being suflicient to close the valve androtatethe actuator and gear train in the reverse direction at such aspeed and through a large enough range that the resulting momentum builtup in the gear train and actuator would be sufficient to cause the valveto rebound from its seat upon striking the same, and means forpreventing such rebounding of the valve from its seat due to themomentum thus imparted to the actuator and gear train during valveclosing movement, said means comprising a brake effective to retard themovement of said actuator and gear train in valve closing direction.

17. A device of the class described, comprising a valve casing having aninlet and an outlet, a partition wall therebetween having a valve seatformed therein, a valve normally biased against the seat to obstructfluid flow from the inlet to the outlet, a rotating actuator for thevalve, a gear train between said actuator and valve whereby the lattermay be opened against its bias by the former upon operative energizationthereof, the bias of the valve being sufficient to close the valve androtatethe actuator and gear train in the reverse direction at such aspeed and through a large enough range that the resulting momen-' tumbuilt up in the gear train and actuator would be suflicient to cause thevalve to rebound from its seat upon striking the same, and means forpreventing such rebounding of the valve from its seat due to themomentum thus imparted to the actuator and gear train during valveclosing movement, said means comprising a lost motion connection betweensaid actuator and said valve and a brake effective to retard themovement of said actuator and gear train in valve closing direction.

NELSON T. BRANCHE.

" CERTIFICATE or coaasc'rror.

Eatent No. 2,052,918.

the above numbered patent requ column, line 9, Letters Patent should bSeptember 1, 193! NELSON BRANCHE.

It is hereby certified that error appears in the printed specificationof claim 13-, for the word "lower" iring correction as follows: Page 4,first read power; and that the s e read with this correction thereinthat the same ma;

conform to the record of the case in the Patent Office.

Signed and sealed this 5th day of January, A. D. 1957.

